xAI is the artificial intelligence company Elon Musk founded to build Grok, a chatbot known for its blunt tone and live access to the X social network. In 2026, SpaceX acquired xAI outright, and the company now operates as a SpaceX subsidiary under the name SpaceXAI.
How xAI got started
Musk founded xAI on March 9, 2023, recruiting around a dozen researchers from Google DeepMind, OpenAI, and Microsoft. He said he wanted to build AI that pursues “the true nature of the universe,” and framed the project partly as a counterweight to what he considered excessive caution in rival chatbots such as ChatGPT and Gemini. The startup grew fast: by 2025 it employed more than 1,200 people, reported roughly $3.2 billion in annual revenue, and trained its models on its own Colossus supercomputer cluster in Memphis, Tennessee.
From standalone startup to part of SpaceX
xAI’s corporate structure changed twice within about a year. In March 2025, xAI acquired X Corp — the company behind the X social network, formerly Twitter — in an all-stock deal that valued X at roughly $33 billion, bringing the chatbot and the social platform under one roof. Then, in February 2026, SpaceX acquired xAI itself in an all-stock transaction that valued SpaceX at about $1 trillion and xAI at roughly $250 billion. xAI’s separate corporate identity wound down over the following months, and by mid-2026 its AI and social media operations had been folded into SpaceX as a division now branded SpaceXAI.
What Grok actually is
Grok is xAI’s flagship chatbot, launched on November 3, 2023. The name comes from the verb “to grok,” coined by science-fiction writer Robert Heinlein to describe understanding something completely and intuitively — a nod to the conversational, sometimes irreverent style Grok aims for. Under the hood, Grok is a large language model family, now in its Grok 4.x generation, trained largely on the Colossus cluster.
Grok’s defining feature is real-time access to X: its “DeepSearch” and “DeeperSearch” modes pull in current posts and web pages to answer questions about unfolding events, something chatbots without a live social feed can’t easily match. Beyond text chat, Grok can generate images through xAI’s Aurora model, produce short video clips via Grok Imagine, transcribe and generate speech in Voice mode, and read images, PDFs, and other file types. xAI also used Grok to build Grokipedia, an AI-written encyclopedia launched in 2025 as an alternative to Wikipedia.
How to try Grok
Grok is available for free, with usage limits, through grok.com, the Grok apps for iOS and Android, and built into the X app. xAI also sells paid consumer tiers with higher usage limits and extra features such as DeepSearch and Grok Imagine — check xAI’s own site for current prices, since consumer plans change over time. Developers who want programmatic access can start with xAI’s API documentation; as of July 2026, the flagship Grok 4.5 model costs $2.00 per million input tokens and $6.00 per million output tokens according to xAI’s model pricing page, with cheaper reasoning-tier models also available.
Why it matters
Grok is one of a handful of frontier chatbots — alongside ChatGPT, Gemini, and Claude — with enough training compute and reach to move pricing and capability benchmarks for the whole industry; its newest release, Grok 4.5, undercuts several rivals on price. Its ownership structure is also unusual: no other major consumer chatbot now sits directly inside a spaceflight company’s balance sheet, which ties Grok’s funding and priorities to SpaceX’s broader business. Grok has also drawn scrutiny over content-moderation lapses, including incidents where it generated hateful or non-consensual content, which is one reason regulators evaluating AI chatbots increasingly ask about a model’s safety testing and guardrails, not just its raw capabilities.
In the news
xAI’s latest model, Grok 4.5, launched at a lower price than Anthropic’s Opus tier, with mixed results across benchmarks — read the brief: Grok 4.5 Launches Cheaper Than Opus, With Mixed Benchmarks.
FAQ
Is xAI the same company as SpaceX?
Yes, as of 2026. SpaceX acquired xAI in an all-stock deal in February 2026, and by mid-2026 xAI’s operations — including Grok and the X social network — were folded into SpaceX under the name SpaceXAI.
Is Grok free to use?
Grok has a free tier through grok.com, the Grok mobile apps, and the X app. Paid plans unlock the full model, higher usage limits, and features like DeepSearch and Grok Imagine.
What makes Grok different from ChatGPT or Gemini?
Grok’s biggest differentiator is live access to X posts through its DeepSearch feature, plus a more casual, less-filtered conversational style. It’s built on the same broad category of large language model as its rivals.
Who runs Grok now?
Michael Nicolls, formerly a SpaceX vice president overseeing Starlink, became president of the AI and social media division (SpaceXAI) in April 2026.